Fabrication of double-shell microcapsule encapsulated with wormwood essential oil and its application in regenerated cellulose fiber

To overcome challenges such as pickling, desulphurization, and viscosity reduction experienced during the integration of microcapsules into viscose spinning solutions through the wet spinning process, this study employed the interfacial polymerization method. Polyurea (PUA) and polyurethane (PU) were used as shell materials, with sliced paraffin and wormwood essential oil (WEO) as core materials, to construct double-shell multifunctional microcapsules (DM). These microcapsules were then introduced into a viscose spinning solution. A functional regenerated cellulose fiber was prepared by incorporating sodium alginate and carboxymethyl cellulose as thickeners. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to analyze the chemical component and structure of the DM. The morphology remained intact without damage after the spinning process using viscose wet spinning. Differential scanning calorimetry (DSC), along with an antibacterial experiment and aroma test, revealed that the functional regenerated cellulose fibers exhibited an enthalpy of crystallization and melting of 24.5 J/g and 35.4 J/g, respectively, and manifested a remarkable 100% inhibition rate against Escherichia coli. The microcapsule-based regenerated fibers prepared in this study significantly advance the application of microcapsules in functional viscose wet spinning processes.

Graphical abstract